// 数组去重
// [1,2,3,1,2,3,{a:1}, [1,2,3], {a:1}, [1,2,3]]
// [1,2,3,{a:1},[1,2,3]]
let arr = [1,2,3,1,2,3,{a:1}, [1,2,3], {a:1}, [1,2,3]]
let arr1 = [1,23,4,4,1,null,null,NaN, NaN]
function uniq(arr) {
  return  Array.from(new Set(arr.map(item => JSON.stringify(item)))).map(item => JSON.parse(item))
}
console.log(uniq(arr1));